Substance use disorders are chronic diseases that have significant adverse medical, psychological, social, and legal consequences due to the high rate of relapse despite treatment. Patients will often need individualized strategies and multimodal treatment to achieve meaningful sobriety and improvement in psychosocial functioning. Aside from individual therapy and medication management, the role of social cohesiveness has shown to be an important factor in keeping a patient engaged in treatment and reducing the risk of relapse. This chapter outlines one type of psychosocial intervention, called Network Therapy, which focuses on incorporating family members, partners, friends, and others (i.e., the patient’s “network”) to support the patient’s abstinence both inside and outside of the therapy environment. This chapter will summarize the existing literature, which outlines the evidence that supports a network-based approach in treating addiction, as well as explain the techniques involved in its practice.